Uhm, I beat the lich, went to the room, not destroyed his source, left and I can't get back there again (and saved over the choice, thinking I could go back) did I lock myself? Also, would I have saved the lich had I destroyed his source?
Once you go in and beat the golem there there is no reason to go back in. I guess I locked the door, but it will not block and content to story. Only need to go in the one time
Right now the litch choice does not have impact on the story. However, I want to make that choice matter more than it does right now. So it might come up in a later update.